SDF is a freely available documentation system designed and developed
by Ian Clatworthy, with help from many others. Based on a simple,
readable markup language, SDF generates high quality output in
multiple formats, all derived from a single document source. Supported
output formats include HTML, PostScript, PDF, man pages, POD, LaTeX,
SGML, MIMS HTX and F6 help, MIF, RTF, Windows help and plain text.
